scholarly journals Meteotsunami occurrence in the Gulf of Finland over the past century

2020 ◽  
Author(s):  
Havu Pellikka ◽  
Terhi K. Laurila ◽  
Hanna Boman ◽  
Anu Karjalainen ◽  
Jan-Victor Björkqvist ◽  
...  
Keyword(s):  
Sea Level ◽  
Meteorological Data ◽  
Convective Available Potential Energy ◽  
Air Pressure ◽  
Gulf Of Finland ◽  
Past Century ◽  
Data Set ◽  
The Past ◽  
Sea Level Oscillations ◽  
The Gulf Of Finland

Abstract. We analyse changes in meteotsunami occurrence over the past century (1922–2014) in the Gulf of Finland, Baltic Sea. A major challenge for studying these short-lived and local events is the limited temporal and spatial resolution of digital sea level and meteorological data. To overcome this challenge, we examine archived paper recordings from two tide gauges, Hanko for 1922–1989 and Hamina for 1928–1989, from the summer months of May–October. We visually inspect the recordings to detect rapid sea level variations, which are then digitized and compared to air pressure observations from nearby stations. The data set is complemented with events detected from digital sea level data 1990–2014 by an automated algorithm. In total, we identify 121 potential meteotsunami events. Over 70 % of the events could be confirmed to have a small jump in air pressure occurring shortly before or simultaneously with the sea level oscillations. The occurrence of meteotsunamis is strongly connected with lightning over the region: the number of cloud-to-ground flashes over the Gulf of Finland were on average over ten times higher during the days when a meteotsunami was recorded compared to days with no meteotsunamis in May–October. On a monthly level, statistically significant differences between meteotsunami months and other months were found in the number of CG flashes, convective available potential energy (CAPE), and temperature. Meteotsunami occurrence over the past century shows a statistically significant increasing trend in Hamina, but not in Hanko.

scholarly journals Meteotsunami occurrence in the Gulf of Finland over the past century

2020 ◽  
Vol 20 (9) ◽  
pp. 2535-2546
Author(s):  
Havu Pellikka ◽  
Terhi K. Laurila ◽  
Hanna Boman ◽  
Anu Karjalainen ◽  
Jan-Victor Björkqvist ◽  
...  
Keyword(s):  
Sea Level ◽  
Meteorological Data ◽  
Convective Available Potential Energy ◽  
Rapid Change ◽  
Air Pressure ◽  
Gulf Of Finland ◽  
Past Century ◽  
Data Set ◽  
The Past ◽  
The Gulf Of Finland

Abstract. We analyse changes in meteotsunami occurrence over the past century (1922–2014) in the Gulf of Finland, Baltic Sea. A major challenge for studying these short-lived and local events is the limited temporal and spatial resolution of digital sea level and meteorological data. To overcome this challenge, we examine archived paper recordings from two tide gauges, Hanko for 1922–1989 and Hamina for 1928–1989, from the summer months of May–October. We visually inspect the recordings to detect rapid sea level variations, which are then digitised and compared to air pressure observations from nearby stations. The data set is complemented with events detected from digital sea level data 1990–2014 by an automated algorithm. In total, we identify 121 potential meteotsunami events. Over 70 % of the events could be confirmed to have a rapid change in air pressure occurring shortly before or simultaneously with the sea level oscillations. The occurrence of meteotsunamis is strongly connected with lightning over the region: the number of cloud-to-ground (CG) flashes over the Gulf of Finland were on average over 10 times higher during the days when a meteotsunami was recorded compared to days with no meteotsunamis in May–October. On a monthly level, statistically significant differences between meteotsunami months and other months were found in the number of CG flashes, convective available potential energy (CAPE), and temperature. Meteotsunami occurrence over the past century shows a statistically significant increasing trend in Hamina, but not in Hanko.

Trends in Chesapeake Bay Sedimentation Rates during the Late Holocene

1990 ◽  
Vol 34 (1) ◽  
pp. 33-46 ◽  
Author(s):  
Joseph F. Donoghue
Keyword(s):  
Sea Level Rise ◽  
Chesapeake Bay ◽  
Sea Level ◽  
Late Holocene ◽  
Tide Gauge ◽  
Past Century ◽  
Sedimentation Rates ◽  
Relative Sea Level ◽  
The Past ◽  
Relative Sea Level Rise

AbstractTrends are discernible in the estimates of late Holocene rates of sedimentation and sea-level rise for the Chesapeake Bay. During most of the Holocene Epoch sedimentation rates and relative sea-level rise were equal, within the limits of measurement, at approximately 1 mm yr−1. Sedimentation rates measured over the past century, however, are nearly an order of magnitude higher, while the rate of relative sea-level rise for the Chesapeake Bay now averages 3.3 mm yr−1, as measured on long-term tide gauge records. When the acceleration in these rates occurred is uncertain, but it appears to have been confined to the past millennium, and probably to the past few centuries. The rapid sedimentation rates recorded during historic time may be a temporary disequilibrium that has resulted from a recent acceleration in the rate of relative sea-level rise.

Coral islands defy sea-level rise over the past century: Records from a central Pacific atoll

Geology ◽  
2015 ◽  
Vol 43 (6) ◽  
pp. 515-518 ◽  
Author(s):  
P.S. Kench ◽  
D. Thompson ◽  
M.R. Ford ◽  
H. Ogawa ◽  
R.F. McLean
Keyword(s):  
Sea Level Rise ◽  
Sea Level ◽  
Past Century ◽  
Central Pacific ◽  
The Past ◽  
Coral Islands

Global Sea Level Trend in the Past Century

Science ◽  
1982 ◽  
Vol 215 (4540) ◽  
pp. 1611-1614 ◽  
Author(s):  
V. GORNITZ ◽  
S. LEBEDEFF ◽  
J. HANSEN
Keyword(s):  
Sea Level ◽  
Past Century ◽  
The Past ◽  
Sea Level Trend ◽  
Global Sea Level

scholarly journals Insights into post-Miocene uplift of the western margin of the Colorado Plateau from the stratigraphic record of the lower Colorado River

Geosphere ◽  
2019 ◽  
Vol 15 (6) ◽  
pp. 1826-1845 ◽  
Author(s):  
Ryan S. Crow ◽  
Keith A. Howard ◽  
L. Sue Beard ◽  
Philip A. Pearthree ◽  
P. Kyle House ◽  
...  
Keyword(s):  
Sea Level ◽  
Colorado River ◽  
Grand Canyon ◽  
Lake Mead ◽  
Basalt Flow ◽  
Data Set ◽  
Continental Scale ◽  
The Past ◽  
River Deposits ◽  
Lower Colorado River

Abstract The spatial and temporal distribution of Pliocene to Holocene Colorado River deposits (southwestern USA and northwestern Mexico) form a primary data set that records the evolution of a continental-scale river system and helps to delineate and quantify the magnitude of regional deformation. We focus in particular on the age and distribution of ancestral Colorado River deposits from field observations, geologic mapping, and subsurface studies in the area downstream from Grand Canyon (Arizona, USA). A new 4.73 ± 0.17 Ma age is reported for a basalt that flowed down Grand Wash to near its confluence with the Colorado River at the eastern end of what is now Lake Mead (Arizona and Nevada). That basalt flow, which caps tributary gravels, another previously dated 4.49 ± 0.46 Ma basalt flow that caps Colorado River gravel nearby, and previously dated speleothems (2.17 ± 0.34 and 3.87 ± 0.1 Ma) in western Grand Canyon allow for the calculation of long-term incision rates. Those rates are ∼90 m/Ma in western Grand Canyon and ∼18–64 m/Ma in the eastern Lake Mead area. In western Lake Mead and downstream, the base of 4.5–3.5 Ma ancestral Colorado River deposits, called the Bullhead Alluvium, is generally preserved below river level, suggesting little if any bedrock incision since deposition. Paleoprofiles reconstructed using ancestral river deposits indicate that the lower Colorado River established a smooth profile that has been graded to near sea level since ca. 4.5 Ma. Steady incision rates in western Grand Canyon over the past 0.6–4 Ma also suggest that the lower Colorado River has remained in a quasi–steady state for millions of years with respect to bedrock incision. Differential incision between the lower Colorado River corridor and western Grand Canyon is best explained by differential uplift across the Lake Mead region, as the overall 4.5 Ma profile of the Colorado River remains graded to Pliocene sea level, suggesting little regional subsidence or uplift. Cumulative estimates of ca. 4 Ma offsets across faults in the Lake Mead region are similar in magnitude to the differential incision across the area during the same approximate time frame. This suggests that in the past ∼4 Ma, vertical deformation in the Lake Mead area has been localized along faults, which may be a surficial response to more deep-seated processes. Together these data sets suggest ∼140–370 m of uplift in the past 2–4 Ma across the Lake Mead region.

scholarly journals Coastal sea level response to the tropical cyclonic forcing in the north Indian Ocean

2014 ◽  
Vol 11 (1) ◽  
pp. 575-611
Author(s):  
P. Mehra ◽  
S. Mohan ◽  
P. Vethamony ◽  
K. Vijaykumar ◽  
T. M. Balakrishnan Nair ◽  
...  
Keyword(s):  
Sea Level ◽  
West Coast ◽  
East Coast ◽  
Meteorological Data ◽  
Linear Regression Analysis ◽  
North Indian Ocean ◽  
Energy Bands ◽  
The West ◽  
Cyclonic Storm ◽  
Sea Level Oscillations

Abstract. The study examines the observed storm-generated sea-level variation due to deep depression (Event-E1) in the Arabian Sea from 26 November–1 December 2011 and a cyclonic storm "THANE" (Event-E2) over the Bay of Bengal during 25–31 December 2011. The sea-level and surface meteorological measurements collected during these extreme events exhibit strong synoptic disturbances leading to storm surge up to 43 cm on the west coast and 29 cm on the east coast of India due to E1 and E2. E1 generated sea level oscillations at the measuring stations on the west coast (Ratnagiri, Verem and Karwar) and east coast (Mandapam and Tuticorin) of India with significant energy bands centered at periods of 92, 43 and 23 min. The surge dome has a duration of 92.6, 84.5 and 74.8 h at Ratnagiri, Verem and Karwar, respectively. However, on the east coast, the sea level oscillations during Thane were similar to those during calm period except for more energy bands centred at periods of ~ 100, 42 and 24 min at Gopalpur, Gangavarm and Kakinada, respectively. Multi-linear regression analysis shows that the local surface meteorological data (daily-mean wind and atmospheric pressure) is able to account for ~ 57% and ~ 70% of daily-mean sea-level variability along the east and west coast of India. The remaining part of variability observed in the sea level may be attributed to local coastal currents and remote forcing.

scholarly journals Storm surges in the Gulf of Finland of the Baltic Sea

2021 ◽  
Vol 66 (4) ◽  
Author(s):  
Evgeny A. Zakharchuk ◽  
◽  
Vladimir N. Sukhachev ◽  
Natal'ia A. Tikhonova ◽  
◽  
...  
Keyword(s):  
Baltic Sea ◽  
Sea Level ◽  
Atmospheric Pressure ◽  
Storm Surges ◽  
Gulf Of Finland ◽  
Northern Coast ◽  
The Baltic Sea ◽  
Wide Range ◽  
The Baltic ◽  
The Gulf Of Finland

The characteristics of storm surges in different regions of the Gulf of Finland in the second half of the XX and the beginning of the XXI centuries were investigated on the basis of tide gauge measurements of sea level, instrumental observations of the wind and data from the reanalysis of meteorological fields. A criterion for identifying storm surges, taking into account spatial changes in their intensity, is proposed. The results indicate that depending on the year and the location of the station, the number of storm surges varies in the Gulf of Finland in a wide range: from 0 - 1 to 16 - 52 cases per year. The average duration of storm surges varies from 6.7 to 9.0 hours, and the maximum reaches 26 to 96 hours. Shown that in recent decades, in most regions, there has been a tendency towards a decrease in the number of storm surges, their dispersion and sea level maximum. The distributions of the probabilities of wind and atmospheric pressure during storm surges are given. Estimates of two-dimensional probability densities indicate that during storm surges, winds blowing from the west and southwest with speeds of 4-13 m / s are most likely. At the northern coast and at the top of the bay, the most probable values of atmospheric pressure during storm surges are 995 hPa. On the southern coast of the Gulf of Finland, atmospheric pressure values of 1005 - 1015 hPa are most likely. The results obtained indicate that the atmospheric pressure over the Gulf of Finland during storm surges is not very low. This is due to the fact that the trajectories of the centers of cyclones causing storm surges pass north of the Gulf of Finland. Analysis of meteorological information also showed the presence of significant negative trends in interannual variations in the dispersion of the horizontal atmospheric pressure gradient, average values and maximums of wind speed. It is concluded that the revealed changes in the characteristics of storm surges are associated with a decrease in the intensity of cyclogenesis in the atmosphere over the Baltic Sea in recent decades.

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